Session Notes for rd1708 Prepared by K. Le Bail, NVI, Inc./GSFC =========================================================== PURPOSE AND GENERAL NOTES =========================================================== GAIA proposal The Laboratory d'Astrophysique de Bordeaux (LAB) subnmitted in 2012 a proposal to observe 195 ICRF2 transfer sources in the context of the GAIA mission. These sources were added to the GSFC monitoring program and 37 sources were scheduled in Gaia-dedicated R&D sessions. In February 2017, we studied the position uncertainties and the observation frequency of the 195 sources of the LAB proposal. Twenty-seven of these sources have a bad observation frequency: they were observed successfully in less than five sessions a year while the LAB requirement was twelve sessions a year. Most of these sources have bad uncertainties compared to the other sources of the set (larger than 50 microas). Three additional sources have good position uncertainties and an observation frequency of five to eleven successful sessions a year. However they are sources that were observed in previous Gaia-dedicated R&D sessions and the concern is that if they are not scheduled in coming dedicated R&D sessions, their observation frequency may drop. The sources scheduled in the Gaia-dedicated R&D sessions scheduled to observe after March 1st, 2017 are these thirty sources. When compared to the previous categories determined by the LAB, one source was in category 1, five sources were in category 2, five sources were in category 3 and nineteen sources were in category 4. In RD1708, we could schedule all thirty sources in the astro mode of sked. One source is scheduled on only one scan (1046-409). We used a maxscan value of 480 seconds. Forty of the good geodetic sources are used as base of a stable sources set and uniform sky coverage. We use the sked flux catalog for all sources. Wettzell will observe INT I17235 during the time from 1815 UT to 1945 UT. The command FILL was used on all stations and on the entire period with a fill_off (buffer offset) of 5 seconds. ----- Parameter listing -------------------------------------- Experiment: RD1708 Description R&D-08/2017 Scheduler: NASA Correlator: SHAO Start: 2017-235-18:00:00 End: 2017-236-18:00:00 Current yyyyddd: 2017235 (2017.64) ( 17989 MJD, WED. 23AUG.) Greenwich sidereal time: 16:08:52 (18:00:00 UT) Sun's RA and DEC: 10h 11.4m 11d 11.5 =========================================================== First observations Observation listing from file ./rd1708.skd for experiment RD1708 Source Start DURATIONS name yyddd-hhmmss Hh Ho Mc T6 Wz 2145+082 17235-180000| 480 480 480 312 480| 1849+670 17235-181000| 84 40 84| 1758-651 17235-181221| 347 347 | 0718+793 17235-181252| 480 40 480| 2155-304 17235-182139| 199 228 228 | 2329-415 17235-182657| 175 175 140 | End of listing. =========================================================== Observation listing from file ./rd1708.skd for experiment RD1708 Source Start DURATIONS name yyddd-hhmmss Hh Ho Mc T6 Wz 0312+100 17236-175900| 55 55 | End of listing. Last observations Observation listing from file ./rd1708.skd for experiment RD1708 Source Start DURATIONS name yyddd-hhmmss Hh Ho Mc T6 Wz 2209+236 17236-175209| 40 110 110| 0137+012 17236-175248| 51 51 | 0211+171 17236-175529| 99 99 | 1920-211 17236-175552| 40 85 85| 1741-038 17236-175837| 78 78 78| 0312+100 17236-175900| 55 55 | End of listing. =========================================================== SKED Summary from file ./rd1708.skd for experiment RD1708 (all scans with at least one subnet station) Average number of obs. per baseline per source(normalized by up-time) = 5.4 Min = 0.0 Max = 68.6 (Baseline T6-Wz on 0823-223) RMS = 8.1 Total time: 1440 minutes ( 24.0 hours). Key: Hh=HARTRAO Ho=HOBART26 Mc=MEDICINA T6=TIANMA65 Wz=WETTZELL Hh Ho Mc T6 Wz Avg % obs. time: 43 37 60 27 55 45 % cal. time: 2 2 2 2 2 2 % slew time: 31 22 27 42 6 26 % idle time: 23 39 10 27 36 27 total # scans: 152 157 196 210 174 177 # scans/hour : 6 7 8 9 7 7 Avg scan (sec): 247 203 266 113 275 220 # data tracks: 32 32 32 32 32 # Mk5 tracks: 32 32 32 32 32 Total TB(M5): 2.4 2.0 3.3 1.5 3.1 2.5 # OF OBSERVATIONS BY BASELINE | Hh Ho Mc T6 Wz Total ----------------------------------- Hh| 71 82 60 55 268 Ho| 12 121 13 217 Mc| 82 160 336 T6| 75 338 Wz| 303 Number of 2-station scans: 196 Number of 3-station scans: 147 Number of 4-station scans: 9 Number of 5-station scans: 4 Total number of scans: 356 Total number of obs: 731 Total integrated obs-time: 144347 Average obs-time: 197.5 Histogram of observation durations Dur: 25 50 75 100 125 150 175 200 225 250 275 300 325 350 375 400 425 450 475 500 #Obs: | 216| 50| 57| 36| 29| 29| 37| 12| 26| 12| 13| 19| 7| 16| 29| 16| 8| 13| 106| Average X-band SNRs by baseline | Hh Ho Mc T6 Wz AVG ---------------------------------- Hh| 31 42 70 61 49 Ho| 24 62 33 48 Mc| 127 121 100 T6| 176 104 Wz| 120 Average S-band SNRs by baseline | Hh Ho Mc T6 Wz AVG ---------------------------------- Hh| 40 27 40 36 35 Ho| 25 42 30 40 Mc| 47 42 39 T6| 57 46 Wz| 44 =========================================================== Recording mode Name Code GEOSX8N 8F Recording mode for: HARTRAO HOBART26 MEDICINA TIANMA65 WETTZELL Mode Tot.Rate Tot.BandW #BBC #bits Barrel Mk341:1 512 Mbits 128 MHz 14 2 NONE Chan.BW #Subpasses Tracks(*fan) Tot.tracks 8.00 MHz 1 32(*1) 32 X-band spanned bw= 720.0 MHz rms spanned bw= 280.4 MHz S-band spanned bw= 140.0 MHz rms spanned bw= 50.9 MHz Effective number of 1-bit channels recorded per sub-pass X S Total 19.13 11.48 30.61 =========================================================== Tape types ID Station Tape length Density Passes Hh HARTRAO Mark5B Ho HOBART26 Mark5A Mc MEDICINA Mark5B T6 TIANMA65 Mark5B Wz WETTZELL Mark5B =========================================================== SNR targets Minimum SNR by baseline for multi-baseline scans X-band (margin 0) S-band (margin 0) X-band (ast_margin 0) S-band (ast_margin 0) Hh Ho Mc T6 Hh Ho Mc T6 Ho 20 Ho 15 Mc 20 20 Mc 15 15 T6 20 20 20 T6 15 15 15 Wz 20 20 20 20 Wz 15 15 15 15 ===========================================================